Wax or varnish for painted MDF?

[indiesearcher]

I know, I know, I should have used eggshell.

But, I had a huge tin of the right colour, in Matt emulsion that would have been thrown away otherwise.

So, I've printed a few shelves and a door in Matt emulsion. It's a chalky finish. What should I use to protect it? Looks lovely as it but not sure it's going to withstand any actual use!

TIA!

Dead Flat Decorator's Varnish should sort you out.

Varnish.

Wax is good for solid unpainted wood.

Thanks both, how many coats varnish do you think??